Multiple human-to-human transmission from a severe case of psittacosis, Sweden, January-February 2013.

Proven transmission of Chlamydia psittaci between humans has been described on only one occasion previously. We describe an outbreak which occurred in Sweden in early 2013, where the epidemiological and serological investigation suggests that one patient, severely ill with psittacosis after exposure to wild bird droppings, transmitted the disease to ten others: Two family members, one hospital roommate and seven hospital caregivers. Three cases also provided respiratory samples that could be analysed by PCR. All the obtained C. psittaci sequences were indistinguishable and clustered within genotype A. The finding has implications for the management of severely ill patients with atypical pneumonia, because these patients may be more contagious than was previously thought. In order to prevent nosocomial person-to-person transmission of C. psittaci, stricter hygiene measures may need to be applied.

Unusual increase of psittacosis in southern Sweden linked to wild bird exposure, January to April 2013.

Free-living wild birds worldwide act as reservoir for Chlamydia psittaci, but the risk of transmission to humans through contact with wild birds has not been widely documented. From 12 January to April 9 2013, a total of 25 cases of psittacosis were detected in southern Sweden, about a threefold increase compared with the mean of the previous 10 years. A matched case-control study investigating both domestic and wild bird exposure showed that cases were more likely than controls to have cleaned wild bird feeders or been exposed to wild bird droppings in other ways (OR: 10.1; 95% CI: 2.1-47.9). We recommend precautionary measures such as wetting bird feeders before cleaning them, to reduce the risk of transmission of C. psittaci when in contact with bird droppings. Furthermore, C. psittaci should be considered for inclusion in laboratory diagnostic routines when analysing samples from patients with atypical pneumonia, since our findings suggest that psittacosis is underdiagnosed.

Little evidence for reversibility of trimethoprim resistance after a drastic reduction in trimethoprim use.

OBJECTIVES: The worldwide rapid increase in antibiotic-resistant bacteria has made efforts to prolong the lifespan of existing antibiotics very important. Antibiotic resistance often confers a fitness cost in the bacterium. Resistance may thus be reversible if antibiotic use is discontinued or reduced. To examine this concept, we performed a 24 month voluntary restriction on the use of trimethoprim-containing drugs in Kronoberg County, Sweden. METHODS: The intervention was performed on a 14 year baseline of monthly data on trimethoprim resistance and consumption. A three-parameter mathematical model was used to analyse the intervention effect. The prerequisites for reversion of resistance (i.e. fitness cost, associated resistance and clonal composition) were studied on subsets of consecutively collected Escherichia coli from urinary tract infections. RESULTS: The use of trimethoprim-containing drugs decreased by 85% during the intervention. A marginal but statistically significant effect on the increase in trimethoprim resistance was registered. There was no change in the clonal composition of E. coli and there was no measurable fitness cost associated with trimethoprim resistance in clinical isolates. The frequency of associated antibiotic resistances in trimethoprim-resistant isolates was high. CONCLUSIONS: A lack of detectable fitness cost of trimethoprim resistance in vitro together with a strong co-selection of other antibiotics could explain the rather disappointing effect of the intervention. The result emphasizes the low possibility of reverting antibiotic resistance once established and the urgent need for the development of new antibacterial agents.

A case of foodborne listeriosis in Sweden.

A 70-year-old woman fell seriously ill overnight with meningitis and was admitted to hospital. Cerebrospinal fluid culture yielded Listeria monocytogenes. One of the first problems in solving a human case of listeriosis suspected to be foodborne is to find the foods likely to have been transmitting L. monocytogenes. Two enrichment procedures and a direct plating procedure were used for isolation of the bacteria from different food items collected from the patient's refrigerator, local retail store and producer. Samples of vacuum-packed products of sliced pork brawn, sliced cooked medwurst and berliner wurst of the same brand harboured L. monocytogenes. Serotyping and restriction enzyme analysis (REA) with pulsed-field gel electrophoresis (PFGE) were used to characterize and compare 41 isolates, including the human strain. At least three clones were present in the foods investigated, and one of these was identical to the human clone. This clone was present in samples of medwurst from the patient's refrigerator and the local retail store. This is, to our knowledge, the first proven foodborne case of listeriosis reported in Sweden.

An epidemiologic study of Lyme disease in southern Sweden.

BACKGROUND: Lyme disease is the most common vector-borne infection in some temperate regions of the Northern Hemisphere. However, for most areas of endemic disease reliable epidemiologic data are sparse. METHODS: Over a one-year period, we conducted a prospective, population-based survey of cases of Lyme disease in southern Sweden. The diagnosis was made on the basis of the presence of erythema migrans at least 5 cm in diameter or characteristic clinical manifestations such as arthritis, neuroborreliosis, and carditis. RESULTS: We identified 1471 patients with Lyme disease, for an overall annual incidence of 69 cases per 100,000 inhabitants. The incidence varied markedly according to geographic region, and there were several areas where disease was widely prevalent. The incidence varied according to age, with the highest rates among people 5 to 9 and 60 to 74 years of age, but not according to sex. The most frequent clinical manifestation was erythema migrans (seen in 77 percent of all cases), followed by neuroborreliosis (16 percent) and arthritis (7 percent). Carditis was rare. A preceding tick bite was reported by 79 percent of the patients. Bites in the head and neck region were more common among children than among adults and were associated with an increased risk of neuroborreliosis. CONCLUSIONS: Lyme disease is very common in southern Sweden, with a relatively high frequency of neurologic complications and arthritis. With the exception of the low incidence of carditis, the pattern of disease we found in Sweden was similar to that reported in the United States.

Retrospective analysis of the efficacy of cefotaxime sodium dosed twice daily. The Swedish experience.

In a Swedish multicenter, comparative, retrospective study, patients with different types of infections--bacteremia-septicemia, genitourinary, intra-abdominal, central nervous system, and lower respiratory tract infections--were randomly selected from the hospital records. Patients treated with cefotaxime twice or three times a day as monotherapy (excluding metronidazole) for at least 1 day (240 cases) were analyzed in terms of clinical and bacteriologic outcome, these results were correlated with the dosing regimen. Similarly high success rates (cure and improvement) at hospital discharge were observed in both group initially treated with cefotaxime 1 g twice daily and 2 g twice daily (97 and 96%, respectively). A total of 73% of patients were initially treated with cefotaxime for only 3 days at most before changing to a lower dose regimen, an alternate intravenous treatment, or oral drug follow-up. Clinical evaluation at hospital discharge revealed a clinical success rate between 87 and 100%, depending on the type of infection.

Seven patients with relapses of Plasmodium vivax or P. ovale despite primaquine treatment.

Seven relapses of Plasmodium vivax or Plasmodium ovale despite standard treatment with primaquine (3.0 mg Kg-1) daily for fourteen days are presented. The majority of patients came from areas outside the countries where resistance to primaquine is well known. The various possibilities of reasons for relapses are discussed.

Binding of fibrinogen degradation products to S. aureus and to beta-hemolytic streptococci group A, C and G.

Binding of fibrinogen degradation products was measured to Gram-positive cocci known to carry receptors for human fibrinogen. Forty-one strains of S. aureus and group A, C and G streptococci were studied. The largest plasmin produced fragment (X-fragment, HMWDP) showed higher binding levels to the bacterial receptors in all four species as compared to intact fibrinogens. The enzymatically produced C-terminal fragment D was strongly reactive, whereas the N-terminal fragment E was non-reactive. Inhibition experiments showed that reactive fragments were bound to the same receptors as fibrinogen. Three chemically-produced and well-characterized fragments from the terminal and the middle portions of the fibrinogen molecule were all negative in binding assays. The binding patterns for fibrinogen and the fragments tested were identical in the four bacterial species tested, S. aureus and group A, C and G streptococci. The results confirm and extend earlier data on similarities between fibrinogen receptors on these Gram-positive bacterial species.